Do all patients with cancer experience fatigue? A longitudinal study of fatigue trajectories in women with breast cancer.

BACKGROUND: Fatigue is a common and expected side effect of cancer treatment. However, the majority of studies to date have focused on average levels of fatigue, which may obscure important individual differences in the severity and course of fatigue over time. The current study was designed to identify distinct trajectories of fatigue from diagnosis into survivorship in a longitudinal study of women with early-stage breast cancer. METHODS: Women with stage 0 to stage IIIA breast cancer (270 women) were recruited before (neo)adjuvant therapy with radiotherapy, chemotherapy, and/or endocrine therapy and completed assessments at baseline; posttreatment; and at 6 months, 12 months, and 18 months of follow-up. Growth mixture modeling was used to identify trajectories of fatigue, and differences among the trajectory groups with regard to demographic, medical, and psychosocial variables were examined. RESULTS: Five distinct trajectories of fatigue were identified: Stable Low (66%), with low levels of fatigue across assessments; Stable High (13%), with high fatigue across assessments; Decreasing (4%), with high fatigue at baseline that resolved over time; Increasing (9%), with low fatigue at baseline that increased over time; and Reactive (8%), with increased fatigue after treatment that resolved over time. Both psychological and treatment-related factors were found to be associated with fatigue trajectories, with psychological factors most strongly linked to high fatigue at the beginning of and over the course of treatment. CONCLUSIONS: There is considerable variability in the experience of fatigue among women with early-stage breast cancer. Although the majority of women report relatively low fatigue, those with a history of depression and elevated psychological distress may be at risk of more severe and persistent fatigue.

Testing a biobehavioral model of fatigue before adjuvant therapy in women with breast cancer.

BACKGROUND: Fatigue is one of the most common and disabling side effects of cancer and its treatment. Although research typically has focused on fatigue that occurs during and after treatment, patients may experience fatigue even before treatment onset. The current study was designed to identify biobehavioral risk factors associated with fatigue before adjuvant therapy in women with early-stage breast cancer. METHODS: Patients with stage 0 to stage IIIA breast cancer (270 women) were recruited before the onset of adjuvant or neoadjuvant therapy with radiotherapy, chemotherapy, and/or endocrine therapy. Host factors that may influence fatigue were identified from an empirically based, biobehavioral model and assessed using self-report questionnaires, medical record review, and blood collection (for genetic data). Fatigue was assessed by questionnaire. Linear regression analyses were used to evaluate the association between host factors and dimensions of fatigue, with general fatigue as the primary dimension of interest. RESULTS: Fatigue was elevated at the pretreatment assessment compared with published controls. Bivariate analyses identified demographic, cancer-related, and biobehavioral correlates of fatigue. In the multivariable model, predictors of general fatigue included younger age, lower educational level, lower cancer stage, and history of childhood maltreatment (all P values <.05), with the full model accounting for approximately 18.4% of the variance in fatigue. Secondary analyses identified common and specific predictors of emotional, mental, and physical dimensions of fatigue. CONCLUSIONS: Among women who have not yet initiated treatment of breast cancer, demographic and psychosocial factors are associated with elevated fatigue and could be used to identify at-risk patients for early intervention.

Yoga for persistent fatigue in breast cancer survivors: a randomized controlled trial.

BACKGROUND: Cancer-related fatigue afflicts up to 33% of breast cancer survivors, yet there are no empirically validated treatments for this symptom. METHODS: The authors conducted a 2-group randomized controlled trial to determine the feasibility and efficacy of an Iyengar yoga intervention for breast cancer survivors with persistent post-treatment fatigue. Participants were breast cancer survivors who had completed cancer treatments (other than endocrine therapy) at least 6 months before enrollment, reported significant cancer-related fatigue, and had no other medical conditions that would account for fatigue symptoms or interfere with yoga practice. Block randomization was used to assign participants to a 12-week, Iyengar-based yoga intervention or to 12 weeks of health education (control). The primary outcome was change in fatigue measured at baseline, immediately post-treatment, and 3 months after treatment completion. Additional outcomes included changes in vigor, depressive symptoms, sleep, perceived stress, and physical performance. Intent-to-treat analyses were conducted with all randomized participants using linear mixed models. RESULTS: Thirty-one women were randomly assigned to yoga (n = 16) or health education (n = 15). Fatigue severity declined significantly from baseline to post-treatment and over a 3-month follow-up in the yoga group relative to controls (P = .032). In addition, the yoga group had significant increases in vigor relative to controls (P = .011). Both groups had positive changes in depressive symptoms and perceived stress (P < .05). No significant changes in sleep or physical performance were observed. CONCLUSIONS: A targeted yoga intervention led to significant improvements in fatigue and vigor among breast cancer survivors with persistent fatigue symptoms.

Acute and Chronic Effects of Adjuvant Therapy on Inflammatory Markers in Breast Cancer Patients.

BACKGROUND: Inflammation contributes to poor behavioral, functional, and clinical outcomes in cancer survivors. We examined whether standard cancer treatments-radiation and chemotherapy-led to acute and persistent changes in circulating markers of inflammation in breast cancer patients. METHODS: A total of 192 women diagnosed with early stage breast cancer provided blood samples before and after completion of radiation and/or chemotherapy and at 6-, 12-, and 18-month posttreatment follow-ups. Samples were assayed for circulating inflammatory markers, including tumor necrosis factor-α (TNF-α) and interleukin (IL)-6, downstream markers of their activity (soluble TNF receptor type II [sTNF-RII], C reactive protein), and other inflammatory mediators (IL-8, interferon-γ [IFN-γ]). Analyses evaluated within-group changes in inflammatory markers in 4 treatment groups: no radiation or chemotherapy (n = 39), radiation only (n = 77), chemotherapy only (n = 18), and chemotherapy with radiation (n = 58). RESULTS: Patients treated with chemotherapy showed statistically significant increases in circulating concentrations of TNF-α, sTNF-RII, IL-6, and IFN-γ from pre- to posttreatment, with parameter estimates in standard deviation units ranging from 0.55 to 1.20. Those who received chemotherapy with radiation also showed statistically significant increases in IL-8 over this period. Statistically significant increases in TNF-α, sTNF-RII, IL-6, IFN-γ, and IL-8 persisted at 6, 12, and 18 months posttreatment among patients treated with chemotherapy and radiation (all P < .05). Patients treated with radiation only showed a statistically significant increase in IL-8 at 18 months posttreatment; no increases in any markers were observed in patients treated with surgery only. CONCLUSIONS: Chemotherapy is associated with acute increases in systemic inflammation that persist for months after treatment completion in patients who also receive radiation therapy. These increases may contribute to common behavioral symptoms and other comorbidities in cancer survivors.

Yoga for persistent fatigue in breast cancer survivors: results of a pilot study.

Approximately one-third of breast cancer survivors experiences persistent fatigue for months or years after successful treatment completion. There is a lack of evidence-based treatments for cancer-related fatigue, particularly among cancer survivors. This single-arm pilot study evaluated the feasibility and preliminary efficacy of a yoga intervention for fatigued breast cancer survivors based on the Iyengar tradition. Iyengar yoga prescribes specific poses for individuals with specific medical problems and conditions; this trial emphasized postures believed to be effective for reducing fatigue among breast cancer survivors, including inversions and backbends performed with the support of props. Twelve women were enrolled in the trial, and 11 completed the full 12-week course of treatment. There was a significant improvement in fatigue scores from pre- to post-intervention that was maintained at the 3-month post-intervention followup. Significant improvements were also observed in measures of physical function, depressed mood, and quality of life. These results support the acceptability of this intervention and suggest that it may have beneficial effects on persistent post-treatment fatigue. However, results require replication in a larger randomized controlled trial.

Yoga reduces inflammatory signaling in fatigued breast cancer survivors: a randomized controlled trial.

BACKGROUND: Yoga is a popular mind-body therapy that has demonstrated beneficial effects on psychological, behavioral, and functional outcomes. However, few studies have investigated effects on inflammatory processes. This study tested the hypothesis that an Iyengar yoga intervention specifically designed for fatigued breast cancer survivors would lead to decreases in inflammation-related gene expression and circulating markers of proinflammatory cytokine activity. METHODS: Breast cancer survivors with persistent cancer-related fatigue were randomized to a 12-week Iyengar yoga intervention (n=16) or a 12-week health education control condition (n=15). Blood samples were collected at baseline, post-intervention, and at a 3-month follow-up for genome-wide transcriptional profiling and bioinformatic analyses. Plasma inflammatory markers and salivary cortisol were also assessed. RESULTS: In promoter-based bioinformatics analyses, the yoga group showed reduced activity of the pro-inflammatory transcription factor nuclear factor kappa B (NF-κB), increased activity of the anti-inflammatory glucocorticoid receptor, and reduced activity of cAMP response element-binding protein (CREB) family transcription factors relative to controls (all ps<.05). There was also a significant intervention effect on the soluble tumor necrosis factor receptor type II (sTNF-RII), a marker of TNF activity; plasma levels of sTNF-RII remained stable in the yoga group, whereas levels of this marker increased in the health education group (p=.028). A similar, non-significant trend was observed for the interleukin 1 receptor antagonist (p=.16). No significant changes in C reactive protein (CRP), interleukin 6 (IL-6), or diurnal cortisol measures were observed. CONCLUSIONS: A 12-week restorative Iyengar yoga intervention reduced inflammation-related gene expression in breast cancer survivors with persistent fatigue. These findings suggest that a targeted yoga program may have beneficial effects on inflammatory activity in this patient population, with potential relevance for behavioral and physical health.

Yoga for cancer patients and survivors.

BACKGROUND: Yoga has been practiced for thousands of years to improve physical and emotional well-being. Empirical research on yoga has been ongoing for several decades, including several recent studies conducted with cancer patients and survivors. METHODS: This review provides a general introduction to yoga and a detailed review of yoga research in cancer. RESULTS: Nine studies conducted with cancer patients and survivors yielded modest improvements in sleep quality, mood, stress, cancer-related distress, cancer-related symptoms, and overall quality of life. Studies conducted in other patient populations and healthy individuals have shown beneficial effects on psychological and somatic symptoms, as well as other aspects of physical function. CONCLUSIONS: Results from the emerging literature on yoga and cancer provide preliminary support for the feasibility and efficacy of yoga interventions for cancer patients, although controlled trials are lacking. Further research is required to determine the reliability of these effects and to identify their underlying mechanisms.